Today, natural resources are becoming scarcer and more required goods, which in the long-term means an increase in production costs of raw materials. The United Nations Environment Programme (UNEP) urges to optimize the development of natural resources in a sustainable way and to maximize the obtaining of raw materials (Corvalán C. et al. (2005) Ecosystems and human well-being: health synthesis: a report of the Millennium Ecosystem Assessment).
A growing technique well known in the prior art that optimizes the use of soil and water resources are crops without soil or hydroponic, by which nutrients dissolved in water are supplied to seeds under appropriate conditions for germination, so that the development of the whole plant under these conditions is finally obtained. Among the advantages of this type of culture in comparison with growth in traditional land it is found the efficient use of nutrients and other inputs, better pest control at lower cost, higher production per square meter planting, among other highlights.
In general industry, it is widely known the commercial value of the aerial parts of plants. For example, grasses such as oats, barley, maize and wheat and their derivatives possess great value for the food industry, and consequently, technological advances are aimed at increasing the development of these. However, there is little knowledge about using roots of these plants. To date, its primary use is as animal fodder, as stated in the “Technical Manual: Green Forage Hydroponic” developed by the Regional Office of FAO for Latin America and the Caribbean, 2001, in which the obtaining of plant biomass from germination of cereals or legumes seeds is taught. To do this, pre-germinated seeds are sown in trays, that is to say, seeds that have been soaked and aired; and then irrigated with water and nutrients for 12 to 14 days to obtain an approximately 30 cm forage with abundant leaves and stems.
A highly innovative alternative to the use of these roots, is as raw material for construction materials. The International patent application PCT/CL2009/000017 discloses a pressed sheet produced from a root mattress obtained from a seed hydroponic culture and an adhesive. This root mattress is essentially obtained by germinating seeds until the leaf component thereof reaches 10 cm height, point at which said leaf component is cut to a 1-1.5 cm height, allowing it to reach 10 cm height again, to cut it back to the height previously mentioned. With this process, the preferred production of the root system over the leaf system is achieved, thus obtaining a root mass which, when drained and dehydrated, allows the obtaining of a support material able to be mixed with an adhesive and then pressed to produce a material that can replace wood, useful in manufacture of panels, boards, planks, among others.
The procedure described above is preferentially used for obtaining root mass from grass seeds germinated in hydroponic conditions. Unfortunately, this method is not efficient in terms of the aerial mass produced, nor the use of resources, since leaves and stems produced must be cut and removed, generating a subsequent loss of resources and time. Therefore, it is required a more efficient methodology for roots production, avoiding unnecessary loss of material and maintaining a high production of mass root, and not aerial mass.